1. Technical Field
The present invention is directed to data storage data processing systems. More specifically, the present invention is directed to a method, apparatus, and computer program product for automatically selecting and migrating data and then responding to requests to access the migrated data transparently to applications that access the data.
2. Description of Related Art
A data storage data processing system typically includes one or more applications that access one or more databases. The applications are directly connected to each one of the databases. Thus, when an application needs to access a database, the application sends requests, such as Create, Retrieve, Update, or Delete requests, to the database using a vendor specific protocol.
When an application needs to access a database, the application will issue a request. The request is in a format, also referred to herein as a vendor specific protocol, which is required by the database that the application is attempting to access. For example, an application might issue a request to access an Oracle database. This request is in an Oracle format. The application expects to receive a result set back from the Oracle database in response to the request in that same Oracle format. The result set the application expects to receive back from the Oracle database will include all of the data requested by application. Thus, the application issues a request directly to a database in a database-specific format. The application then expects to receive a response from the database that includes a complete result set of all of the data requested by the application. The application expects the response to also be in the database-specific format.
It may be desirable to migrate data from one database to another. When data is migrated, the applications must be made aware of the new location of the data. When an application needs to access data where some of that data has been migrated, the application itself must retrieve the data from each location by issuing a request for data from each database in each database's database-specific format. For example, if the data is located in two different databases, the application must issue a first request for data from the first database in the first database's specific format and also issue a second request for data from the second database in the second database's specific format. The application will then receive a partial result set from each source that the application must assemble to form a complete result set. The data to satisfy the application's needs comes from two sources. The application must assemble the data responses from each database.
Therefore, a need exists for a method, apparatus, and computer program product for automatically selecting and migrating data and then responding to requests to access the migrated data transparently to applications that access the data.